Role of Explants and NAA on Callus Induction of Potato ( Solanum tuberosum)

An experiment was conducted to study the role of NAA and different explants on callus induction of potato varieties. There were three factors such as variety (Diamant, Heera and Cardinal), explants (leaves and internodes) and NAA levels (0, 2, 3, 4, 5 mg L -1). The experiment was laid out in complete randomized design with three replications. Minimum 6-8 days was required for callus initiation of internode of Cardinal in 3 mg L -1 NAA while the maximum 22-25 days was required for internode of Cardinal in 5 mg L -1 NAA. Both the leaf and internode of Heera produced 100% callus while Cardinal produced minimum callus (37.7 and 20.8% for leaf and internode, respectively) in 5 mg L -1 NAA. Neither leaf nor internode produced callus without NAA. Internode of Diamant, Heera and Cardinal produced 100% compact calli in 4, 3 and 5 mg L -1 NAA respectively. Leaf of Diamant without NAA produced the highest weight (0.667 g) of callus after one month. After two months, internode of Cardinal showed the highest weight (0.205 g) of calli in 3 mg L -1 NAA. Therefore, the present protocol has the potential for the rapid multiplication of true-to-type clones without changing the genetic fidelity.